The present invention relates to a surface acoustic wave device and a communication terminal using the same.
Hitherto, a Japanese Patent Laid-Open No. 2005-229455 has proposed “a surface acoustic wave device whose piezoelectric substrate is 5 μm to 100 μm thick, joint surface is roughly polished, and supporting substrate consists of silicon of which both surface layers are oxidized to be 0.1 μm to 40 μm thick” as a surface acoustic wave device “formed from a piezoelectric substrate and a supporting substrate smaller in expansion coefficient than the piezoelectric substrate, both substrates being bonded together with an adhesive layer.”